What the 38103 alarm means

The controller lost communication with the serial measurement board (SMB) in the robot base — position feedback from the absolute encoders is unavailable. This fault ranks high in our ABB IRC5 / OmniCore (RobotWare) service records, and the first site inspection usually finds the source.

Most common causes

  • SMB cable disconnected or damaged at the X2 connector or robot base
  • Broken SMB board
  • Resolver/cable damage
  • Corroded or loose connector pins
Field note: The first cause shows up most on real machines, so verify it before you go further.

Step-by-step field fix

  1. Power down and reseat the SMB cable at both the cabinet X2 and the robot base
  2. Inspect the cable for damage along the dress pack
  3. Measure continuity and check connector pins for corrosion
  4. Swap in a known-good SMB board if the cable checks out
  5. After repair, update revolution counters and recalibrate if needed
Safety first: For ABB 38103, when communication drops, controller and external devices can disagree about state; at reconnect, external axes or tooling may act on stale commands. On site you may look at after confirming power-off the first step yourself: Power down and reseat the SMB cable at both the cabinet X2 and the robot base. Beyond that it is external axes and tooling interlocks work - leave it to a professional.

How we diagnose communication alarms on site

ABB 38103 belongs to the communication family. On ABB 38103 the failing stage is IRC5 / OmniCore - the data link: fieldbus, Ethernet, cabinet-to-body communication and external device interfaces. We start reading ABB 38103 at the FlexPendant event log and system diagnostics, with the cabinet status LEDs.

The chain involved in ABB 38103 runs: physical layer (cable / connector / shield) -> link layer (protocol / baud / node ID) -> application layer (data mapping / handshakes).

If SMB cable disconnected or damaged at the X2 connector or robot base on ABB 38103 is intermittent and a reboot buys a while: Intermittent drops that a reboot clears for a while are usually interference. Power cables sharing a trunk with communication cables, poor common grounding between drives and robot, or a shield landed at both ends forming a ground loop all produce exactly this. We check spacing between communication and power runs, single- versus double-ended shield landing, and the cabinet earth-bar connections. The fix is often re-routing and re-grounding - no hardware - but it needs a coordinated stop.

Field notes on this page cover ABB 38103 (Communication with SMB Interrupted); written by the Henghuan repair team, updated 2026-10-01.

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Related Communication alarms

10012 — Guard Stop (Protective Stop) State 10013 — Emergency Stop State 20032 — Revolution Counters Not Updated 50053 — Too Large Revolution Counter Difference 50056 — Joint Collision 50057 — Joint Not Synchronized
Same family: this code belongs to the Communication alarms family - the page collects all Communication-family codes we have handled, with the common inspection order and spares.
Other brands: we also keep field-fix libraries for Yaskawa · Universal Robots · Kawasaki and more — see the complete alarm code hub.

Frequently asked questions

QWhat does the ABB 38103 alarm mean?

The controller lost communication with the serial measurement board (SMB) in the robot base — position feedback from the absolute encoders is unavailable. This fault ranks high in our ABB IRC5 / OmniCore (RobotWare) service records, and the first site inspection usually finds the source. ABB 38103 sits in the communication family; on our work orders the highest-frequency trigger for this code is "SMB cable disconnected or damaged at the X2 connector or robot base".

QCan I clear a ABB 38103 alarm myself?

Whether ABB 38103 clears on its own depends on the outcome of "Power down and reseat the SMB cable at both the cabinet X2 and the robot base". Finish the flow with "After repair, update revolution counters and recalibrate if needed" to confirm ABB 38103 - do not skip it. If that step is clean, the second most frequent cause on ABB 38103 is "Broken SMB board". Do not chase takt through a repeating ABB 38103. Left alone, communication faults tend to graduate from repairable to must-replace.

QFor communication alarms like ABB 38103, how long does a site visit take?

The commonest causes we see on ABB 38103 are "SMB cable disconnected or damaged at the X2 connector or robot base, Broken SMB board, Resolver/cable damage", so we stock the van against those. For ABB 38103 specifically, we carry common bus cables, connectors, termination resistors and shield terminals. For ABB 38103, communication work is about tracing the physical link segment by segment; most cases close in one visit. Before we roll, tell us what ABB 38103 shows on the FlexPendant event log and system diagnostics, with the cabinet status LEDs and what the machine was doing - phone or video triage is free.

This page on ABB 38103 was written by the Henghuan Robotics repair team from field service experience. Alarm descriptions are our own summary for troubleshooting reference and may vary by controller and software version — when in doubt, check your ABB documentation or contact us. Henghuan is an independent service provider, not affiliated with or endorsed by ABB.